Researchers improve solid-state battery design

Cornell University researchers have advanced the design of solid-state batteries by transforming liquid electrolytes into solid polymers inside the electrochemical cell.

By Chris Vavra April 3, 2019

Cornell researchers have advanced the design of solid-state batteries, which are safer and more energy-dense than lithium-ion batteries.

By starting with liquid electrolytes and then transforming them into solid polymers inside the electrochemical cell, the researchers take advantage of both liquid and solid properties to overcome key limitations in current battery designs. This research coincides with industries looking for rechargeable battery technology that can safely power next-generation technology such as electric cars, autonomous vehicles, and robots.

Apart from improving battery safety, solid-state electrolytes enable next-generation batteries that utilize metals such as lithium and aluminum as anodes for achieving far more energy storage than today’s state-of-the-art battery technology. In this context, the solid-state electrolyte prevents the metal from forming dendrites, a phenomenon that can short circuit a battery and lead to overheating and failure.

“Imagine a glass full of ice cubes: Some of the ice will contact the glass, but there are gaps,” said Qing Zhao, a postdoctoral researcher, in a press release announcing the discovery.” She is also lead author on the study, “Solid-State Polymer Electrolytes With In-Built Fast Interfacial Transport for Secondary Lithium Batteries.”

“But if you fill the glass with water and freeze it, the interfaces will be fully coated, and you establish a strong connection between the solid surface of the glass and its liquid contents,” she added. “This same general concept in a battery facilitates high rates of ion transfer across the solid surfaces of a battery electrode to an electrolyte without needing a combustible liquid to operate.”

Solid-state batteries, in spite of their potential advantages, have not been produced at a large scale. Reasons include high manufacturing costs and the previous designs’ poor interfacial properties. A solid-state system also circumvents the need for battery cooling by providing stability to thermal changes.

“Our findings open an entirely new pathway to create practical solid-state batteries that can be used in a range of applications,” said senior author Lynden Archer in a press release.

According to Archer, the strategy for creating solid polymer electrolytes is exciting because it shows promise for extending cycle life and recharging capabilities of high-energy-density rechargeable metal batteries.

“Our approach works for today’s lithium ion technology by making it safer, but offers opportunity for future battery technology,” Archer said.

Chris Vavra, production editor, Control Engineering, CFE Media,

Author Bio: Chris Vavra is web content manager for CFE Media and Technology.